It is well known to support pipes and other elongate bodies with structural support channel. Pipe clamps may be used to support the pipe to the channel. Existing two-piece pipe clamp assemblies include a pair of clamp halves whereby each clamp half is positioned within the channel about the pipe and connected together using a threaded nut and bolt assembly through flanges in the clamp halves. Tightening of the nut and bolt assembly urges the clamp halves together securing the pipe to the channel.
The clamping forces employed to secure the clamp halves about the pipe may tend to bend or otherwise damage the pipe upon securing the pipe to the channel. In order to prevent such damage during securement, the art has seen the use of pipe cushions which may be positioned between the pipe and the pipe clamp.
For example U.S. Pat. No. 470,698 shows a bottom-opening pipe cushion in which the pipe is inserted through a lower slot therein. Bottom-opening pipe cushions of this type are designed for use with a single-member pipe clamp. These pipe cushions would not be suitable for use with a two-piece pipe clamp as the cushion would then exhibit a tendency to be pulled open at the insertion slot when a two-piece pipe clamp is tightened about the pipe cushion. Two-piece pipe clamps tend to pinch the bottom-opening pipe cushion body at its top surface, causing the pipe cushion body to be pulled about the surface of the pipe. The pulling of the pipe cushion body about the pipe surface results in the insertion slot being pulled open and may result in the pipe cushion body being lifted from the pipe at its top surface, resulting in further discontinuities between the pipe cushion and the inserted pipe.
In order to accommodate the use of two-piece pipe clamps, the art has developed improvements in pipe cushions. An example of an improved pipe cushion used in combination with a pipe clamp is shown in U.S. Pat. No. 4,967,148. The pipe cushion shown therein includes a generally cylindrical body formed from deformable material. The pipe is inserted into the cushion body through a slot in the upper end thereof opposite the slot. The slot divides the cushion body into two halves which must be pried open to load the pipe into the cushion. Once loaded into the cushion, the pipe clamp halves are secured about the pipe cushion to secure the pipe to the structural channel.
One disadvantage in the pipe cushions of the prior art is their failure to provide substantial continuous contact about the full circumference of an inserted pipe. United States U.S. Pat. Nos. 3,778,537 and 5,018,260 provide examples of various difference designs of such pipe cushions. Typically, the discontinuous contact is a result of an overly wide insertion slot which is too large to be closed by tightening of the clamp halves. Other times, the discontinuous contact is the result of an elongate notch provided on the interior surface of the pipe cushion so that the insertion slot may be more easily pried open for pipe insertion. The '148 patent provides an example of a pipe cushion having a weakened or open location in the pipe cushion body which facilitates flexing or deformation of the body thereabout. Constructions such as that of the '148 patent introduce a further area of discontinuity, in addition to the slotted opening, which lessens the protection to the pipe from the pipe clamp.
Another disadvantage in the pipe cushions of the prior art is the need to pry open those pipe cushions having very narrow insertion slots. Pipe cushions attempting to maximize the amount of contact between the pipe cushion and the inserted pipe can be cumbersome to install as they require greater deflection when receiving a pipe therein.
It is therefore desirable to provide an improved pipe cushion for use in a support assembly which may be easily fitted onto the pipe and which provides substantially continuous protective support of the pipe between the structural channel and the pipe clamp assembly.